The present invention relates to an information carrier obtained by supporting on a substrate at least one fitting for, for example, storing, displaying or processing information, and a process for producing the same.
Various information carriers have been proposed which are obtained by supporting one or more parts such as IC chips on a substrate, store information, and give information to a reader-writer or receive information therefrom. Such information carriers are used for, for example, storing personal information on deposits, insurances, commutation tickets, licences, health, identification cards, etc., information on product management in factories, and information on commodity management in the commodity distribution field, or the employment of the information carriers for such purposes is investigated.
FIG. 29 and FIG. 30 are diagrams showing an example of such an information carrier which has been known: FIG. 29 is a partially sectioned plan view of the information carrier, and FIG. 30 a sectional view taken along the line 30--30 of FIG. 29. In these drawings, the symbol 100 shows an IC module; the symbol 101 a coil connected to the IC module 100; the symbol 102 a substrate supporting the IC module 100 and the coil 101; the symbol 103 a resin constituting the substrate 102; the symbol 104 a reinforcer for the resin 103; and the symbols 105 and 106 cover sheets attached to the right and reverse, respectively, sides of the substrate 102.
As is clear from these drawings, in this example of the information carrier, the IC module 100 and the coil 101 are placed in a cut-out hole 104a made in the reinforcer 104, and the space in the cut-out hole 104a is filled with the resin 103, which is infiltrated into the reinforcer 104, whereby the substrate 102 is formed. Since this example of the information carrier thus comprises the reinforcer 104 having the cut-out hole 104a, and the IC module 100 and the coil 101 placed in the cut-out hole 104a, a position in the substrate 102 at which the coil 101 is set can be accurately regulated by adjusting the size of the cut-out hole 104a to a suitable size for the coil 101, so that the efficient receipt of electric power from an external equipment and the efficient transmission of signals from or to the external equipment are possible.
The above well-known example of the information carrier, however, involves the following problem: since the IC module 100 and the coil 101 are placed in the cut-out hole 104a made in the reinforcer 104 and the resin 103 inside and outside the cut-out hole 104a is cured, the strength inside the cut-out hole 104a having no reinforcer 104 is low, so that when the information carrier receives an irregular external force, stress is centered on the inside of the cut-out hole 104a, resulting in easy cracking of the substrate 102.
Said information carrier also involves the following problem: since reinforcers 104 different in the size of the cut-out hole 104a have to be prepared depending on the sizes of the IC module 100 and the coil 101 which are to be placed in the cut-out hole 104a, a complicated production process is required when various information carriers are produced in the same line.
In addition, in the above well-known example of the information carrier, the reinforcer 104 is made of, for example, woven fabric obtained by plain weave of glass fiber, so that when the cut-out hole 104a is made by cutting the reinforcer 104, the glass fiber is frayed and stuck out of the cut surface to cause the following phenomenon: as shown in FIG. 31, the frayed glass fiber 107 juts out into the inside of the cut-out hole 104a or extends above or below the reinforcer 104.
When the frayed glass fiber 107 juts out into the inside of the cut-out hole 104, the following disadvantage is brought about: as shown in FIG. 32, the thickness of a portion where the IC module 100 and/or the coil 101 overlaps with the glass fiber 107 exceeds the thickness of the substrate 102, so that the surface flatness of the substrate 102 and hence that of the cover sheets 105 and 106 are deteriorated. When the frayed glass fiber 107 extends above or below the reinforcer 104, the thickness of such a portion is larger than that of the other portion of the substrate 102, so that the flatness of the cover sheets 105 and 106 is deteriorated. When the flatness of the cover sheets 105 and 106 is deteriorated, the beautiful appearance and the ease of handling are deteriorated, resulting in a decreased commercial value. Furthermore, in the case of an information carrier in which, for example, a photograph of owner's face is printed on the surface of the cover sheet 105 or 106 after the production of the information carrier, there is a disadvantage in that the photograph of the face cannot be clearly printed.
Since the woven fabric obtained by plain weave of glass fiber is hardly compressible in the direction of the thickness, pressing of the substrate 102 cannot remove the thickness nonuniformity of the substrate 102 and moreover tends to destroy the IC module 100 and the coil 101. The above-mentioned disadvantage can be removed by stopping the fraying, for example, by hardening and fixing the glass fiber 107 frayed and stuck out of the cut surface with a resin before inserting the IC module 100 and the coil 101 into the cut-out hole 104a, but a production process of the information carrier becomes complicated as much, resulting in an increased production cost of the information carrier. Therefore, this method cannot be said to be a preferable method.
The present invention was made for solving such problems and objects thereof are to provide an information carrier having a high resistance to external force (e.g. flexure) and such a flat surface that it is excellent in beautiful appearance and permits good necessary printing, and to provide a production process which makes it possible to produce such an information carrier easily in high yield.